"viral infections: e.g. HIV, hepatitis B, hepatitis C, EBV"
"Prognostic staging uses the TNM system, depending on location:"
"PTC"
"ERCP"
"Inflammatory bowel disease (IBD) 17"
"liver fluke infestation: Opisthorchis spp. and Clonorchis spp. 18,20"
"NB: There is variability in nomenclature in the literature, as perihilar cancers often span the vague and variable boundary between intrahepatic and extrahepatic bile ducts. For example, intrahepatic cholangiocarcinomas are sometimes subclassified into peripheral and hilar types 16."
"Mass-forming: tumours will be a homogeneous mass of intermediate echogenicity with a peripheral hypoechoic halo of compressed liver parenchyma. They tend to be well delineated but irregular in outline and are often associated with capsular retraction 2 which, if present, helps distinguish cholangiocarcinomas from other hepatic tumours."
"Periductal infiltrating: tumours typically are associated with altered calibre bile duct (narrowed or dilated) without a well-defined mass."
"Intraductal: tumours are characterised by alterations in duct calibre, usually duct ectasia with or without a visible mass. If a polypoid mass is seen, it is usually hyperechoic compared to surrounding liver 2."
"Mass-forming: these are typically homogeneously low in attenuation on non-contrast scans, and demonstrate heterogeneous minor peripheral enhancement with gradual centripetal enhancement 2,3. The rate and extent of enhancement depend on the degree of central fibrosis 2. Again, capsular retraction may be evident. Calcification may be seen in ~20% 24. The bile ducts proximal to the mass are typically dilated."
"Periductal infiltrating: intrahepatic tumours appear as regions of duct wall thickening or of the periductal parenchyma, with altered calibre of the involved duct (usually narrowed). These are most common at the hepatic hilum. They tend to be longer than benign strictures (i.e. approximately 20 mm in length) and show contrast enhancement. There is usually some proximal (i.e. peripheral) dilatation of the biliary tree."
"Intraductal: these are characterised by alterations in duct calibre, usually duct ectasia with or without a visible mass. If a polypoid mass is seen, it is hypoattenuating on pre-contrast imaging and demonstrates enhancement 2."
"For a mass-forming cholangiocarcinoma consider the following:"
"For a periductal infiltrating cholangiocarcinoma consider the following:"
"For an intraductal cholangiocarcinoma consider:"
"Direct cholangiography is a blanket term for any imaging obtained with intra-biliary tree contrast and includes:"
Expected headings
"Mass-forming"
"Periductal infiltrating"
"Intraductal"
"Contrast-enhanced ultrasound"
"Direct cholangiography"
"Surgical resectability"
"Periductal infiltrating: intrahepatic tumours appear as regions of duct wall thickening or of the periductal parenchyma, with altered calibre of the involved duct (usually narrowed). These are most common at the hepatic hilum. They tend to be longer than benign strictures (i.e. approximately 20 mm in length) and show contrast enhancement. There is usually some proximal (i.e. peripheral) dilatation of the biliary tree."